Theoretical Yield Example Problem - Chemistry Homework

Theoretical Yield Example Problem - Chemistry Homework This example problem demonstrates how to predict the amount of product produced from a given amount of reactants. Problem Given the reactionNa2S(aq) 2 AgNO3(aq) → Ag2S(s) 2 NaNO3(aq)How many grams of Ag2S will form when 3.94 g of AgNO3 and an excess of Na2S are reacted together? Solution The key to solve this type of problem is to find the mole ratio between the product and the reactant.Step 1 - Find the atomic weight of AgNO3 and Ag2S.From the periodic table:Atomic weight of Ag 107.87 gAtomic weight of N 14 gAtomic weight of O 16 gAtomic weight of S 32.01 gAtomic weight of AgNO3 (107.87 g) (14.01 g) 3(16.00 g)Atomic weight of AgNO3 107.87 g 14.01 g 48.00 gAtomic weight of AgNO3 169.88 gAtomic weight of Ag2S 2(107.87 g) 32.01 gAtomic weight of Ag2S 215.74 g 32.01 gAtomic weight of Ag2S 247.75 gStep 2 - Find mole ratio between product and reactantThe reaction formula gives the whole number of moles needed to complete and balance the reaction. For this reaction, two moles of AgNO3 is needed to produce one mole of Ag2S.The mole ratio then is 1 mol Ag2S/2 mol AgNO3Step 3 Find amount of product produced.The excess of Na2S means all of the 3.94 g of AgNO3 will be used to complete the reaction.grams Ag2S 3.94 g AgNO3 x 1 mol AgNO3/169.88 g AgNO3 x 1 mol Ag2 S/2 mol AgNO3 x 247.75 g Ag2S/1 mol Ag2SNote the units cancel out, leaving only grams Ag2Sgrams Ag2S 2.87 g Ag2S Answer 2.87 g of Ag2S will be produced from 3.94 g of AgNO3.

Emphatic Expressions - Strong Collocations

Emphatic Expressions - Strong Collocations Adverb intensifiers can be used to emphasize verbs. These emphatic expressions are used in formal English in written documents and when speaking at formal occasions such as business meetings and giving presentations. Here is a list of some of the most common of these intensifiers. Intensifiers categorically - in every manner, without reservedeeply - strongly, with much feelingenthusiastically - with great joyfreely - without hesitationfully - completely, without any doubthonestly - truly believingpositively - without any doubtreadily - without hesitationsincerely - with best wishesstrongly - with convictiontotally - without any doubtutterly - without any doubt Using Intensifiers in Sentences Here are example sentences of each intensifier which can be noted in italics. I categorically dont want to spend any time doing that homework.She deeply feels the need to treat others with respect.The children played soccer enthusiastically.You can find local newspapers freely available all over town.Alice does her work quickly and honestly.Youll find that many people readily accept low pay due to current levels of unemployment.  I can sincerely recommend John for the job.  She strongly presents her point of view.  Hes totally sure hes ready to take the test.Drake thinks its utterly useless to spend any more time on the project.   Using Intensifiers   Generally speaking, be very careful with your use of intensifiers. These are strong words, and they make a strong impression. When used carefully, these adverbs can really underline something you feel strongly about. However, if used too often, the intensifiers can begin to sound rather aggressive. Its best to use these words with great care, and only when you really want to make a point.   Words Used with Intensifiers These are generally used with specific verbs to create emphatic expressions. These intensifier verb combinations are strong collocations. Collocations are words that are always or often used together. Here is a list of the intensifier verb combinations which make up the emphatic expressions: Intensifier Verb Collocations Emphatic Expression categorically deny - In no way did I do something.deeply regret - I am strongly sorry for my actions.enthusiastically endorse - I happily, and with my whole heart believe in something.freely appreciate - I certainly understand something.fully recognize - I am aware of some situation.honestly believe - I think something is true without any doubt.positively encourage - I hope that you do something very strongly.readily endorse - I believe in something someone else does without hesitation.sincerely hope - I honestly want something for someone else.strongly recommend - I really think you should do something.totally reject - I refuse to believe or do in any case.utterly refuse - I completely do not want to do or believe. Here are example sentences for each of these emphatic expressions: We categorically deny any involvement in the scandal.I deeply regret the loss of your loved one.I enthusiastically endorse the local cancer society.We freely appreciate the current difficulties in this market.I fully recognize your need to improve your career.I honestly believe he is telling the truth.Wed like to positively encourage you to buy this stock.Our company readily endorses his run for office.I sincerely hope you are able to find employment soon.Id like to strongly recommend you visit an employment specialist.They totally reject any compromise in these negotiations.Im afraid I utterly refuse to believe anything he says. Heres a short quiz. Choose the correct intensifier for each gap. He ______ appreciates your interest in the company.Jennifer _________ hopes you telephone her soon.The boss _________ rejects any changes to worker contracts.The thief _________ denied any wrongdoing in the crime.Many people __________ believe Ronald Reagan was a great president.Doug _____________ recommends having steak at that restaurant.Unfortunately, the CEO ____________ refused to make any compromises.Many young people ______________ endorse the new president.If you want to succeed, youll have to ___________ recognize the need to study long hours.She ______________ regrets any problems she may have caused.   Answers freely appreciatessincerely hopestotally rejectscategorically deniedhonestly believehighly recommendsutterly refusedenthusiastically endorse  fully recognizedeeply regrets